By eye, Mercury is a relatively uniform grey with splotches of variation in brightness. But MESSENGER’s sensitive cameras have filters on them which isolate different colors, and when put together and enhanced they show subtle color changes on the planet’s face. These colors are almost certainly due to changes in the composition of the rocks on the surface… in other words, MESSENGER can do mineralogical studies from space!

In this closeup view, younger terrain on the left is yellower, while older features appear blue. We know the area on the left is young because it’s smooth; it hasn’t been around long enough to get bombarded from space by comet and asteroid impacts. On the right, the material that appears blue may have been ejected by the impact that formed the crater on the right.

Remember, these colors are not nearly this striking to the eye! It’s only because we can enhance MESSENGER’s color information that these color features are visible.

Sadly, the flyby was so fast that scientists can’t really interpret these colors and tag them to different kinds of minerals. But MESSENGER is going to settle into orbit around Mercury in 2011, and once it does, these cameras will map the surface to their hearts’ (well, CPUs’) content, providing us with incredible details of the content of this dinky, battered, roasted planet.

This was not a telecon but a real press conference (“space science update”, with the speakers sitting around a table) shown live on NASA TV – where they said it’ll be re-run several times later today. I “tweeted” it live, sans the visuals, of course.

Very nice images. I’m reminded that Mercury is not the moon. Lunar-like, yes; grey to the eye and heavily cratered, but really a very different world. On the surface, up close its likely even more unusual.
Some day, if humans or robots actually land on the surface, I think they’d find many unusual local features.

The schedule is insertion in Mach 2011. But, we fortunately have another flyby next September to tide us over. I can’t wait. If the past two flybys are any indication, there is going to be some great science once it actually is taking measurements for long periods of time.

I understand that this image is a composition from multi-spectral images? Do you know if the raw data for those images is going to be available to general public? In my research group we have been working with hyper-spectral images for quite a while and I would LOVE to work with those images.

Impactors on Mercury must be travelling between 4.2 and 115.6 kilometers per second. That compares to a range of 11.2 to 71.9 kilometers per second for the earth. Thus, the minimum impact velocity on Mercury is 38 percent of what it is for the earth and the maximum impact velocity on Mercury is 161 percent of what it is for the earth. Thus, the same mass impactor can smack Mercury with 2.6 times the maximum kinetic energy as it can hit the earth with. That means Mercury can get clobbered really bad.

See that crater with the bright rays in the middle of the picture? That’s Kuiper crater and it has a diameter of 60 kilometers. It would have taken a 3.1 kilometer wide rocky asteroid travelling at 30 km/sec to create that guy. The details are as follows:

Cratering effects:
Width of transient crater at the surface = 3.83E1 km
Depth of transient crater at the surface = 1.35E1 km
Volume of transient crater at the surface = 7.81E3 km^3
Width of final crater at the surface = 6.02E1 km
Depth of final crater at the surface = 1.59E0 km
Volume of final crater at the surface = 2.26E3 km^3

According to the main Yahoo page news section, “NASA probe shows Mercury spewed ‘dark blue material'”. At least the linked to article explains reality. They just labeled it with “NASA probe shows Mercury more dynamic than thought” and explained that it wasn’t really blue.

I wonder how much dust litters the surface of Mercury? Could it all have melted into larger chunks?

Meteoric dust is one of the primary inhibiters to Lunar construction. It gets into everything and degrades moving components. Not particularly good for human lungs, either. HAving said that, I can think of a half dozen ways to protect both,,,

One SciFi story I read years ago, proposed using AI ‘bots to build power generating stations on the light side of Mercury and a large particle accelerator on the dark side, to generate and store anti matter, the ultimate fuel for reaction drives. I wonder if EXXON will ever get into such energy sources.?(,,,mumbles abstractedly, while checking investment portfolio,,,)

I hope all those proud scientists here have the intelligence to visit this site and really, really *think* about the challenges Mercury poses us mortal men and women with our guesswork theories versus the Eternal Word.

Thank you Fidelus, my eyes have seen the glory and I am going to repent of the evils of evolution and sinful astronomy. If I was American I would be lining up now to vote for McCain/Palin – blessed be their names….
Nah, not really.

Obviously that webpage was written by a biologist because they keep referring to evolutionists saying this and that about planetary formation. I think the word they’re looking for is astronomer or astrophysicist. There is so much wrong with that article I don’t know where to begin. The most obvious error? Pluto is a planet? Puhleeese.

Are the great circle arcs, lines of ejecta or are they artifacts of the data storage?
I presume they’re not meridians drawn (by NASA) from the mercury pole; so how are the poles for habitation–are there craters at the poles deep enough to be comfortable (sun never rises)? One would need a heat absorber/radiator to get rid of the last of the heat from the day and transport heat up for the worst of the nights.

@John Lerch “Are the great circle arcs, lines of ejecta or are they artifacts of the data storage? I presume they’re not meridians drawn (by NASA) from the mercury pole; so how are the poles for habitation–are there craters at the poles deep enough to be comfortable (sun never rises)?”

The rays are real. They appear to be coming from the crater at the top of the image. It must be one of the more recent craters to form. The axial tilt of Mercury is the smallest of any planet in the solar system. It is only 0.035 degrees. This means that there should be a rather large area at the poles in which the crater bottoms are always in shadow and the crater rims are always in sunshine.

“This means that there should be a rather large area at the poles in which the crater bottoms are always in shadow and the crater rims are always in sunshine.”

More specifically, a 1-kilometer wide rocky asteroid impacting at 30 km/sec at an angle of 45 degrees leaves an impact crater on Mercury that is 22.2 km wide and 1.18 km deep. If such an impact crater were to occur within 6 degrees of latitude of either the Mercurian north pole or south pole (i.e., Mercurian latitude is greater than 84 degrees North or less than 84 degrees South) then the bottom of such a crater will be in perpetual darkness. This area where the crater can be and be dark at the bottom represents 0.5 percent of the total surface area of Mercury.